Investigation and Comparison of the Effect of Saffron Petals Hydroalcoholic Extract with Metformin and Glibenclamide on Serum Glucose, HbA1c and Insulin Levels in Streptozotocin-Induced Diabetic Rats

Introduction: Chemical drugs administered to control and treat diabetes mellitus are mostly with side effects and this has caused a daily increasing expansion in the use of alternative treatment methods including medicinal herbs. The present study has been conducted to investigate the effect of saffron petal hydroalcoholic extract on serum glucose, insulin and glycosylated hemoglobin (HbA1c) levels and compare it with the effects of metformin and glibenclamide in diabetes-induced rats. Materials and Methods: A total number of 35 male Wistar rats (200 +/- 20 g) were assigned to seven 5-animal groups: control group (normal), diabetic group (Streptozotocin 60 mg/kg/body weight) and five other diabetic groups (receiving saffron petals hydroalcoholic extract in 100, 200 and 300 mg/kg doses and glibenclamide in 5 mg/kg and metformin in 500 mg/kg, respectively). The experiment lasted eight weeks and blood samples were collected from all the rats in the end of the study. Results: 100 and 200 mg/kg dosages of saffron petal extract caused significant reductions in serum glucose levels in contrast to the diabetic groups (P<0.01 and P<0.05, respectively). All three dosages of saffron petals extract, 100, 200 and 300 mg/kg, were found significantly reducing serum HbA1c level in diabetic groups as well as significantly increasing serum insulin level (P<0.001, P<0.001 and P<0.05, respectively). The diabetic groups treated with glibenclamide and metformin, as well, brought about significant reductions in serum glucose and HbA1c levels (P<0.01 and P<0.001, respectively) and significant increase in serum insulin levels (P<0.001). Results: 100 and 200 mg/kg dosages of saffron petal extract caused significant reductions in serum glucose levels in contrast to the diabetic groups (P<0.01 and P<0.05, respectively). All three dosages of saffron petals extract, 100, 200 and 300 mg/ kg, were found significantly reducing serum HbA1c level in diabetic groups as well as significantly increasing serum insulin level (P<0.001, P<0.001 and P<0.05, respectively). The diabetic groups treated with glibenclamide and metformin, as well, underwent significant reductions in serum glucose and HbA1c levels (P<0.01 and P<0.001, respectively) and significant increase in serum insulin levels (P<0.001). The impact rate of saffron petal extract administered in a dosage of 100 mg/kg on serum insulin level elevation was higher than such drugs as glibenclamide and metformin. Conclusion: Saffron petal, like glibenclamide and metformin, is interestingly capable of influencing high serum levels of glucose and HbA1c and insulin, especially in low dosages, and it can be an appropriate solution to the control of diabetes.